Means for recording sound



Nov. 22, 1927. 1,649,847

V. C.VJ.` NIGHTINGALL v MEANS Fon RECORDING soUND Filed Sept. 4. 1924 Patented Nov. 22,1921;

UNITED STATES PATENT oFF1cE.

vICToR CrIARLEs JCHN NICIITTNCALLLCE HEIDELBERG, NEAR MELBOURNE,

VICTORIA, AUSTRALIA. l

MEANS FOR RECORDING SOUND.

Application filed September 4, 1924, Serial No. 735,953, and in Australia March 20, 1924.

This invention refers to means for the recording of sound on blank discs or C linders, endless bands or ribbons and has or 'its object to provide a considerable advance in this art, such advance being characterised by cheapness in production, the elimination of several costly and involved steps at present necessarily employed thereby' expediting the production of records in a marked deee. Y grFor convenience of description and illustration l will describe my invention as for use with recording surfaces of the disc type.

Sound records are ordinarily made or inscribed -on wax disks sufliciently soft to yield to the Vibration of the recording device. Such a disk is too soft for direct use in making duplicate so that an electro-plate is made from it for reproduction purposes. The present invention seeks to avoid the necessity and ex ense of making the electro-plate, and wlth this object 1n view, 1t

proposes to record the sound directly upon a disk sufficiently hard to be repeatedly subjected to the stylus of the reproducing device without deterioration.

The invention relates particularly to a* heated recording stylus which softens its pathon the relatively hard record enablin the latter to take the impress of the soun vibrations.

Figure 1 is a front view of a stylus and diaphragm embracing this invention.

Figure 2 is a side elevation thereof.

Figure 3 is a View showing stylus.

When applyin the invention to disc records for gramop ones, the diaphragm 34 is connected to a ltone arm 26 and has connected thereto an insulated bridge piece 35 so that one arm 36 of a stylus may be placed in the holder 37 where the needle in a sound box is usually placed, the arm 38 having been previously bent as at 39 to form a point 40 where the two arms join the point 40 projecting in the same position to that which the needle would occupy in a recording sound box.

The arm 36 as above described passes into the holder 37 and is retained 'therein by means of the screw 37 whilst the arm 38 passes into the holder 41 which is insulated by means of mica washers 37b from the bridge piece 35.

4The point 40 of the stylus is ground or otherwise shaped to form the desired depth and breadth of track upon the recording i pliances as described, it is obvious that under ordinary conditions a helical .track will be formed laterally on the face of the blank `5 as herein described in reference tothe ordina-ry type of reproducer, and the helical track thus formed provides the mechanical traversing means for pulling a tone arm, diaphragm and fitments across the record for the reproduction of sound.

The cutting stylu's or needle being in position isv then heated in any suitable manner which will permit of localizing and maintainin the maximum heat at the point 40 of trac -forming stylus and although various methods of applying heat vto obtain this essential result may be attempted 4it is preferred to use electrical energy and cause it to flow from one end 42 ofv the stylus arm 38 through the actual point 40 and to the other side 36 thus permitting the greatest heat ener being delivered at the actual cutting pomt of the stylus.

The cutting point 40 having been made slightl less 1n cross section than the arms 36 an 38 of the stylus, the point 40 will therefore' oier more electrical resistance to the vheating current and will be the hottest point of the stylus, the dimensions of the point 40 and the arms 36 and 38 being so proportioned that when thepoint 40 is at a temerature of about 1000 Fahr. the supporting arms 36-38 are at a much lower temperature that will allow them Ito retain their hardness for the mechanical purpose of supporting the heated point 40 while functioning on the recording surface.

The electrical energy so flowing causes the point 40 to become heated and by adjusting to a temperature closely related to the temperature at which the blank 5 becomes plastic and causing this track forming stylus to move in contact with the surface of the noW-revolvingblank 5, on speaking, singing or otherwise causing sound vibrations to flow into a suitably constructed voice 'focussing device or funnel as 44, a record of the sound waves will be faithfull engraved upon the recording surface whic may immedlately be transferred to a talking produced. y

machine und the voice or othersound re What I claim as my invention and de-l sire to secure by'Letters Patent isz- 8 1. Means for ca ing out the process of recordin sound vibrations upon a bla-nk by a beate stylus comprising a diaphragm responsive bridge-piece, electric connectors insulated from one another terminals o an electric und supported said bridge-piece said connectors being circuit. and a `*stylus having Iarmsv removably attachable to said connectors for 4closin through said stylus.y f

g the circuit ing out the process trically conductive diaphragm-responsive bridge piece, electric connectors, one grounded upon said bridge piece and the other insulated therefrom, said connectors bein thel terminals of an electric circuit, a stylus avmg arms coacting with said connectors, and means for removably securlng sald stylus Vto said connectors.

Signed at Melbourne, Victoria, Australia.

VICTOR CHARLES JHN NIGHTINGALL. 

